constants VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS, USRSTACK and PS_STRINGS.
This is mainly so that they can be variable even for the native abi, based
on different machine types. Get stack protections from the sysentvec too.
This makes it trivial to map the stack non-executable for certain abis, on
machines that support it.
- Remove all instances of the mallochash.
- Stash the slab pointer in the vm page's object pointer when allocating from
the kmem_obj.
- Use the overloaded object pointer to find slabs for malloced memory.
v_tag is now const char * and should only be used for debugging.
Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.
Suggested by: phk
Reviewed by: bde, rwatson (earlier version)
address space yet.
- Check whether a process is a system process prior to dereferencing
its p_vmspace. Aio assumes that only the curthread switches the address
space of a system process.
The process allocator now caches and hands out complete process structures
*including substructures* .
i.e. it get's the process structure with the first thread (and soon KSE)
already allocated and attached, all in one hit.
For the average non threaded program (non KSE that is) the allocated thread and its stack remain attached to the process, even when the process is
unused and in the process cache. This saves having to allocate and attach it
later, effectively bringing us (hopefully) close to the efficiency
of pre-KSE systems where these were a single structure.
Reviewed by: davidxu@freebsd.org, peter@freebsd.org
s/SNGL/SINGLE/
s/SNGLE/SINGLE/
Fix abbreviation for P_STOPPED_* etc flags, in original code they were
inconsistent and difficult to distinguish between them.
Approved by: julian (mentor)
in the original hardwired sysctl implementation.
The buf size calculator still overflows an integer on machines with large
KVA (eg: ia64) where the number of pages does not fit into an int. Use
'long' there.
Change Maxmem and physmem and related variables to 'long', mostly for
completeness. Machines are not likely to overflow 'int' pages in the
near term, but then again, 640K ought to be enough for anybody. This
comes for free on 32 bit machines, so why not?
pmap_zero_page() and pmap_zero_page_area() were modified to accept
a struct vm_page * instead of a physical address, vm_page_zero_fill()
and vm_page_zero_fill_area() have served no purpose.
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
by pmap_qenter() and pmap_qremove() is pointless. In fact, it probably
leads to unnecessary pmap_page_protect() calls if one of these pages is
paged out after unwiring.
Note: setting PG_MAPPED asserts that the page's pv list may be
non-empty. Since checking the status of the page's pv list isn't any
harder than checking this flag, the flag should probably be eliminated.
Alternatively, PG_MAPPED could be set by pmap_enter() exclusively
rather than various places throughout the kernel.
vm_page_sleep_busy() with vm_page_sleep_if_busy(). At the same time,
increase the scope of the page queues lock. (This should significantly
reduce the locking overhead in vm_object_page_remove().)
o Apply some style fixes.
swapped in, we do not have to ask for the scheduler thread to do
that.
- Assert that a process is not swapped out in runq functions and
swapout().
- Introduce thread_safetoswapout() for readability.
- In swapout_procs(), perform a test that may block (check of a
thread working on its vm map) first. This lets us call swapout()
with the sched_lock held, providing a better atomicity.
except for the fact tha they are presently swapped out. Also add a process
flag to indicate that the process has started the struggle to swap
back in. This will be needed for the case where multiple threads
start the swapin action top a collision. Also add code to stop
a process fropm being swapped out if one of the threads in this
process is actually off running on another CPU.. that might hurt...
Submitted by: Seigo Tanimura <tanimura@r.dl.itc.u-tokyo.ac.jp>
vm_page_rename() from vm_object_backing_scan(). vm_page_rename()
also performs vm_page_deactivate() on pages in the cache queues,
making the removed vm_page_deactivate() redundant.
handler in the kernel at the same time. Also, allow for the
exec_new_vmspace() code to build a different sized vmspace depending on
the executable environment. This is a big help for execing i386 binaries
on ia64. The ELF exec code grows the ability to map partial pages when
there is a page size difference, eg: emulating 4K pages on 8K or 16K
hardware pages.
Flesh out the i386 emulation support for ia64. At this point, the only
binary that I know of that fails is cvsup, because the cvsup runtime
tries to execute code in pages not marked executable.
Obtained from: dfr (mostly, many tweaks from me).
the loadav. This is not real load. If you have a nice process running in
the background, pagezero may sit in the run queue for ages and add one to
the loadav, and thereby affecting other scheduling decisions.
when VM_ALLOC_WIRED is specified: set the PG_MAPPED bit in flags.
o In both vm_page_wire() and vm_page_allocate() add a comment saying
that setting PG_MAPPED does not belong there.
that pre-zeroes free pages.
o Remove GIANT_REQUIRED from some low-level page queue functions. (Instead
assertions on the page queue lock are being added to the higher-level
functions, like vm_page_wire(), etc.)
In collaboration with: peter
Use lmin(long, long), not min(u_int, u_int). This is a problem here on
ia64 which has *way* more than 2^32 pages of KVA. 281474976710655 pages
to be precice.
to return a wired page.
o Use VM_ALLOC_WIRED within Alpha's pmap_growkernel(). Also, because
Alpha's pmap_growkernel() calls vm_page_alloc() from within a critical
section, specify VM_ALLOC_INTERRUPT instead of VM_ALLOC_SYSTEM. (Only
VM_ALLOC_INTERRUPT is implemented entirely with a spin mutex.)
o Assert that the page queues mutex is held in vm_page_wire()
on Alpha, just like the other platforms.
vm_page_zero_idle() instead of partially duplicated implementations.
In particular, this change guarantees that the number of free pages
in the free queue(s) matches the global free page count when Giant
is released.
Submitted by: peter (via his p4 "pmap" branch)
o Assert that the page queues lock is held in vm_page_unwire().
o Make vm_page_lock_queues() and vm_page_unlock_queues() visible
to kernel loadable modules.
_vm_map_lock_read(), and _vm_map_trylock(). Submitted by: tegge
o Remove GIANT_REQUIRED from kmem_alloc_wait() and kmem_free_wakeup().
(This clears the way for exec_map accesses to move outside of Giant.
The exec_map is not a system map.)
o Remove some premature MPSAFE comments.
Reviewed by: tegge
page-zeroing code as well as from the general page-zeroing code and use a
lazy tlb page invalidation scheme based on a callback made at the end
of mi_switch.
A number of people came up with this idea at the same time so credit
belongs to Peter, John, and Jake as well.
Two-way SMP buildworld -j 5 tests (second run, after stabilization)
2282.76 real 2515.17 user 704.22 sys before peter's IPI commit
2266.69 real 2467.50 user 633.77 sys after peter's commit
2232.80 real 2468.99 user 615.89 sys after this commit
Reviewed by: peter, jhb
Approved by: peter
and kmem_free_wakeup(). Previously, kmem_free_wakeup() always
called wakeup(). In general, no one was sleeping.
o Export vm_map_unlock_and_wait() and vm_map_wakeup() from vm_map.c
for use in vm_kern.c.
I do not know why this didn't panic my box, but I have most certainly
been using it:
peter@overcee[3:14pm]~src/sys/i386/i386-110> sysctl -a | grep zero
vm.stats.misc.zero_page_count: 2235
vm.stats.misc.cnt_prezero: 638951
vm.idlezero_enable: 1
vm.idlezero_maxrun: 16
Submitted by: Tor.Egge@cvsup.no.freebsd.org
Approved by: Tor's patches are never wrong. :-)
TLB problem when bouncing from one cpu to another (the original cpu will
not have purged its TLB if the it simply went idle).
Pointed out by: Tor.Egge@cvsup.no.freebsd.org
Approved by: Tor is never wrong. :-)
threaded VM pagezero kthread outside of Giant. For some platforms, this
is really easy since it can just use the direct mapped region. For others,
IPI sending is involved or there are other issues, so grab Giant when
needed.
We still have preemption issues to deal with, but Alan Cox has an
interesting suggestion on how to minimize the problem on x86.
Use Luigi's hack for preserving the (lack of) priority.
Turn the idle zeroing back on since it can now actually do something useful
outside of Giant in many cases.
pmap_swapin_proc/pmap_swapout_proc functions from the MD pmap code
and use a single equivalent MI version. There are other cleanups
needed still.
While here, use the UMA zone hooks to keep a cache of preinitialized
proc structures handy, just like the thread system does. This eliminates
one dependency on 'struct proc' being persistent even after being freed.
There are some comments about things that can be factored out into
ctor/dtor functions if it is worth it. For now they are mostly just
doing statistics to get a feel of how it is working.
vm_mmap() as well as the GETATTR etc.
- If the handle is a vnode in vm_mmap() assert that it is locked.
- Wiggle Giant around a little to account for the extra vnode operation.
